Tiny Home Village With No Hydrant Nearby
A nonprofit proposes a 20-unit tiny-home village for 40 formerly homeless residents on 1.5 acres. The site has an existing 6-inch dead-end water main; the nearest public hydrant is 650 ft from the site entrance; access is a 20-ft-wide private drive 300 ft long with no turnaround; units are 120 sq ft each, spaced 10 ft apart; the community building is 1,200 sq ft with a commercial kitchen and a 40-person assembly room. The applicant proposes no sprinklers in the tiny homes, smoke alarms only, and a 1-hour exterior wall on one side. The planning commission asks the fire marshal to recommend conditions. The applicant argues each tiny home is a single-family dwelling and therefore exempt from sprinklers. The fire marshal must decide occupancy classification, water supply and access requirements, and separation.
1. How would you classify the tiny homes and the community building under the IBC, and why does that classification drive the sprinkler and egress analysis?
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Start with use, not with the applicant's label. The tiny homes are sleeping units for residents, so they are most likely Group R-2 if the occupancy is permanent, or Group R-1 if it is transient. The community building with a commercial kitchen and a 40-person assembly room is likely Group A-3, unless it qualifies as an accessory use; either way, it is not a dwelling unit. Classification matters because the sprinkler threshold for R-2 is generally tied to the number of dwelling units in a building, while separate tiny homes spaced 10 ft apart may be treated as separate buildings. That does not end the analysis: the village has shared access, shared water supply, and a population that may include people with mobility or cognitive impairments. The community building is a separate assembly occupancy and should be evaluated on its own egress, cooking suppression, and alarm requirements. The egress analysis must consider the path from each unit to the public way, not just the unit door, and the 300-ft drive with no turnaround affects both evacuation and fire apparatus access.
2. Evaluate the proposed water supply and access. What specific conditions would you recommend?
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The 650-ft hydrant distance and 6-inch dead-end main are the most serious deficiencies. The code generally expects a hydrant within a specified distance of the buildings and enough fire flow for the occupancy; a 6-inch dead end serving 20 residential units plus a community building is unlikely to provide both the flow and the redundancy needed. Require either an on-site hydrant connected to a looped or improved main, or a documented fire-flow test showing adequate flow at the required residual pressure, with a hydrant located so that every unit is within the applicable hose-lay distance. For access, a 300-ft dead-end drive normally requires an approved turnaround, and 20 ft of width is the minimum for fire apparatus; require a turn-around or a second access point, clear width, overhead clearance, and load-bearing surfaces. Also require address markings, gate access, and a plan for ambulance access. These conditions are not cosmetic: without water and turnaround, a fire in one unit can extend to adjacent units before the first line is charged.
3. How would you handle the applicant's argument that each tiny home is exempt from sprinklers, and what alternative mitigation would you accept if sprinklers are not installed?
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Acknowledge the argument but test it against the actual building configuration. If each tiny home is truly a separate building with the required fire separation distance, the R-2 sprinkler threshold may not apply to each unit in the same way it would to a 20-unit apartment building. However, the 10-ft spacing, the shared drive, the limited water supply, and the vulnerable population are exactly the conditions that make a fire spread beyond the unit of origin. If sprinklers are not installed, require a package that compensates for the missing suppression: interconnected smoke alarms or a monitored alarm in each unit, a 1-hour exterior wall or maintained separation that prevents radiant ignition, ember-resistant vents, a 5-ft noncombustible zone around each unit, and sprinklers in the community building and any shared storage. Consider residential sprinklers in units designated for residents with mobility impairments. Document the alternative as a performance-based approval with conditions, not as a waiver, and require the owner to maintain the alarm and separation features.